Diagnosing pulmonary embolism: establishing and consolidating the role of spiral CT

Abstract

In the Antelope study availability, use and diagnostic accuracy of spiral CT in patients clinically suspected of PE was investigated. This study was divided in two separate phases, starting with a prospective evaluation of available diagnostic techniques part of the diagnostic consensus strategy in The Netherlands in a specifically designed algorithm. Phase I showed that in a direct comparison with the gold standard sensitivity and specificity of spiral CT is too low to endorse its role as a single test to exclude pulmonary embolism. Also spiral CT had a limited added value as a second procedure following ventilation-perfusion scintigraphy. The accuracy of CT was significantly better in cases with interobserver agreement and good image quality. The available data of phase I was used for a cost-effectiveness analysis. Combined with recent literature data two new strategies were proposed and studied independently. Phase II showed in a prospective clinical management study that spiral CT can be used safely as a first line test to rule out pulmonary embolism in clinically suspected patients. It is also possible to reliably determine an alternative diagnosis in 25% of all patients. A new questionnaire showed that since 1997 the use of spiral CT has increased considerably